Heat pump DIY, anyone installed?

R-Carpenter

Our propane furnace is 20+ years old so we are looking in to either replacement or changing the system all together. After getting a few estimates, each made my eyes roll, I am considering installing MrCool or similar DIY heat pumps.
Has anyone done it already? Any opinions?

Eggguy

I heat and cool my shop with a Mr. cool 5 ton heat pump. I was able to switch it to 4 ton mode to achieve 18 seer and I am very happy with it. The outside unit, the lineset, and the air handler were all precharged. I had a problem with my first lineset because it did not have quick connectors in the box. I called Ingrams water and air in Kentucky and they promptly sent me a new lineset. The units are made in China by Gree. I talked to several HVAC guys and they said they were good quality. The small amount of air that gets introduced by the line connectors is not enough to worry about. I am told that any moisture will be absorbed by the internal in line dryer. My cousin in Louisiana bought a Mr. Cool Diy minisplit for his garage, per my recommendation, and is very happy with it. If you buy from Ingrams try asking for a free T shirt or hat.

Kornbread

Installed 4Senville mini-splits in the past couple years. 28seer ($1100)&26seer($1k). For cooling they are as efficient as our geotherm heat pump and in the shoulder seasons they heat efficiently, but when outdoor temps drop to real winter time temps, the geotherm kicks their butts.

I bought a cheap vacuum pump, IIRC $140, to pull the lines down.

DanW

I’m in the process of installing a Home Depot sourced Pioneer mini-split. I went with the most efficient of their current offerings because they qualify for the 30% federal tax credit. Also check your local utility for rebates.

Mine is going in a 14x24’ detached garage that I’m turning into a proper woodworking shop. Just waiting for interior paint to dry out for a few days before installing interior unit and running the refrigerant lines. Neighbor is a general contractor and is doing that for a case of beer.

Eggguy

The liquid payment option.

tajanes

When up and running, plz let us know how this works when the snow falls (temp falls). And, how you will be setting the overnight temp vs the in-shop (when working in the shop) temp - thx.

DanW

From doing some reading before buying, it seems like these new units have a heater on the condensate lines that extend low temp performance without using the old school resistive heating/toaster oven approach. The older style justifiably has a bad rep for low temp performance. I will have a decent idea on actual performance when I get end of December bill.

My unit has a ‘freeze protection’ mode which keeps a set point of ~50 Fahrenheit instead of 60+. I plan to use that during heating season. If I’m actively working that temp will be reasonable and keep the delta Temp lower for $$$ savings. I can always bump that as needed for finishing.

tajanes

@DanW said:
I will have a decent idea on actual performance when I get end of December bill.

My unit has a ‘freeze protection’ mode which keeps a set point of ~50 Fahrenheit instead of 60+. I plan to use that during heating season. If I’m actively working that temp will be reasonable and keep the delta Temp lower for $$$ savings. I can always bump that as needed for finishing.

My little shop is one of my attached garage spots (floor heated). When I'm going in to the shop, getting temp to 50 works just fine for me- sweater weather, as the floor under my feet feels warm. I have min temp currently set at 44 degrees (and I may take that down a couple more?). Last eve we hit 6 degrees outdoors and the far unit floor turned on for a bit.

Kornbread

@DanW said:
From doing some reading before buying, it seems like these new units have a heater on the condensate lines that extend low temp performance without using the old school resistive heating/toaster oven approach. The older style justifiably has a bad rep for low temp performance. I will have a decent idea on actual performance when I get end of December bill.

My unit has a ‘freeze protection’ mode which keeps a set point of ~50 Fahrenheit instead of 60+. I plan to use that during heating season. If I’m actively working that temp will be reasonable and keep the delta Temp lower for $$$ savings. I can always bump that as needed for finishing.

From what I've seen, the low-temp units use a resistive heating strip ... maybe you are looking at upscale models and they have something other than a resistive strip? The units without the extra heating strip often like to run defrost cycles which also cut into overall efficiency. In a thread somewhere, it was said the ones without the defrost heating strips can actually pull a small amount of heat out of the house to defrost the outside unit. If either the geothermal unit, or mini-splits go out, we have redundancy, although, if it were to come another ice storm and take the grid out, we would use the mini-splits as they have no starting surge and are easier on the solar system.

Put 2mini-splits in last year and 2more 2years ago. So far, no issues. Easy to install. No contractor needed. It's surprising technology has advanced far enough that it costs roughly the same to run an air to air mini-split as our ~15yr old geothermal heat pump, during the summer. Winter heating swings way in favor of the geothermal heat pump.

Might want to read up on any rebates your poco, local, or state government might offer. Be aware, sometimes it not only must meet a certain efficiency level, but also a minimum btu. We received about 35% back on the geothermal unit in rebates and tax breaks, and a couple hundred $ back on the air to air mini-splits.